Exposing a single layer of berries in sample tray in the sun carried out drying experiments in July 2002. To increase the water permeability of mulberry skin, the samples were dipped into ethyl oleate solution (AEEO) at room temperature for 1 min. The AEEO was prepared by mixing water, K2CO3 (5%) and ethyl oleate (2%). Mulberry berries, about 200 g, were spread over tray. The treated berries were distributed uniformly in a single layer in the sample tray, and then placed immediately in the sun. In addition, no pretreatment samples (UNTREATED) were also dried at same conditions. Moisture loss was measured at 2 h intervals during drying for determination of the drying curves by a Mettler balance (model BB3000), which the measurement range was 0–3000 g with an accuracy of ฑ0.1 g. No measurement was made during night. Drying was continued until the sample reached the desired moisture level (17%, wet basis). Dried samples were cooled and packed in low density polyethylene (LDPE) bags, which were sealed with heat. The experiments were repeated twice and the average of the moisture ratio at each value was used for drawing the drying curves.